Future-Proofing the World’s Coral Reefs

Even though they cover less than a quarter of one percent of the Earth’s surface, coral reefs are nursery habitats for as much as 25% of the world’s species of fish. According to the United Nations Environment Programme, the leading global authority on the environment, as many as a half billion people depend on the food those reefs provide, the protection they offer from coastal erosion and the enormous economic benefits they make possible by attracting as many as 70 million tourists a year.

Due to a variety of factors, including rising global temperatures, approximately 14% of those coral reefs died between the years 2009 and 2014 — at rates faster than their ability to renew themselves or science’s ability to restore them. However, promising new research by a University of Virginia environmental scientist suggests that there may be solutions not only for restoring coral reefs at a much faster rate but also for making them more resilient to future threats.

“Coral populations are declining globally, and there are a variety of different forces at play,” said Matthew Reidenbach, an environmental sciences professor in UVA’s College and Graduate School of Arts & Sciences. “In some locations it’s urban and coastal development that causes a lot of added nutrients that go into the water; in other places, it’s overfishing of the fish that eat the algae that grows on the coral.”

The combination leads to excessive growth of algae that overwhelms the coral reefs where they would normally form a mutually beneficial relationship. Ultimately, an excess of algae blocks the sunlight and consumes the oxygen coral species need to survive.

Ocean acidification, caused by the absorption of carbon dioxide emitted by the burning of fossil fuels, is also taking a toll. According to the U.S. Environmental Protection Agency, the ocean acidity has increased by about 30 percent since the Industrial Revolution and is expected to increase by an additional 40 percent over the next 75 years.

The result is a combination of both local and global threats that are leading to growing rates of coral bleaching.

“In Australia, for example, we’re seeing pristine reefs, that weren’t impacted by humans before, starting to bleach and die,” Reidenbach said. “The goal is to begin to prepare to future proof the world’s coral against the challenges they’re going to be facing.”

There are two approaches to solving the problem, Reidenbach explained.

“You can look at the problem locally by doing things like limiting nutrient inputs into the water, but you can also look at growing new corals,” Reidenbach said. “Turns out, growing new corals is a super slow process.”

Two Imperfect Solutions

As an expert in the restoration of marine ecosystems, Reidenbach has been highly successful as one of the leaders of the effort to regrow eelgrass along Virginia’s Eastern Shore — a project that is helping restore the region’s scallop population, a vital economic resource that was almost completely wiped out by disease and a devastating hurricane in the 1930s — but he admits that much about the work of growing coral is still a mystery.

“We’ve done restoration for other types of marine life really well, but for coral reefs, we still haven’t quite figured it out,” Reidenbach said.

One approach involves breaking off pieces of coral, growing the fragments in a lab and then putting them back into the ocean.

“The big problem with that is that they’re all genetically identical, which means they’re more susceptible to disease and other similar threats because, genetically, they’re not very diverse, and we know that diversity is the key to survival,” Reidenbach said.

An interest in more practical ways of restoring coral populations led Reidenbach to reach out to Dr. Samia Sarkis, a marine biologist and director of the Living Reefs Foundation, a Bermuda-based nonprofit working to repair damaged coral reefs.

Sarkis studies the sexual process by which corals reproduce which creates larvae that are released into the water and then find places to settle and grow. Reidenbach is interested in understanding how the larvae decide where to settle, what conditions are most beneficial for their growth and how they use crevices in their environment for protection from predators.

“In the laboratory, we’re trying to create tiles with surfaces that will enhance that settlement process,” Reidenbach said. “And once that’s done in the laboratory, we’re interested in how to do that on a large scale in the ocean to create the ideal conditions for new coral to grow.”

Reidenbach is also interested in focusing on species of coral that are more resistant to heat or can be selected for traits that make them genetically more heat tolerant.

“The problem is that no one knows how to do that, and that’s where we are now,” Reidenbach said.

His students are working on computational models and simulations, but there’s still a lot that they need to understand about the basic science of coral reproduction before they can launch extensive restoration efforts. The problem is creating unique challenges in the search for funding to keep the research moving.

A Coral Catch-22

Outside funding has been an important ingredient in helping Reidenbach’s team travel to their research site in Bermuda and purchase the supplies and instruments needed for their lab, but due to the nature of their work, Reidenbach explained, he’s found himself in a blind spot when it comes to securing the interest of large-scale funders.

“We sent a proposal to the National Science Foundation saying we want to understand larval settlement because we want to do restoration, but they kicked it back saying they don’t usually fund restoration projects, and then a lot of the nonprofits interested in restoration feel we aren’t far enough along in understanding the basic science,” Reidenbach said. “It’s hard to get support for projects like this where the ultimate goal is restoration, but you need to better understand how to do it before the restoration can begin.”

Enter Pete Ten Eyck, an alumnus of the College and UVA’s Darden School of Business. The commercial real estate executive was already a supporter of several ocean conservation organizations, but he wanted to have a more direct financial impact on the efforts to address issues like global warming and ocean acidification that have visibly degraded the underwater landscapes he has come to know and love as a SCUBA diver.

An inquiry from Ten Eyck led to a desperately needed source of funding that is allowing Reidenbach to collect the data he needs as he makes the case for funding on a larger scale.

Ten Eyck worked with the College Foundation, the fundraising arm of the College of Arts & Sciences, to develop the Fairfax Marine Research Fund to support innovative research ideas and coral restoration projects like Reidenbach’s, to increase the Department of Environmental Sciences’ research impact and to create research opportunities for both graduate and undergraduate UVA students.

“The idea was that establishing a fund at UVA would be more efficient than giving to a traditional charity, which is typically 75-85% efficient,” Ten Eyck said. “As the administrative costs are already covered by the University, gifts or contributions are 100% efficient — all going to impact the environment. The activity is transparent; you know exactly what your gift is doing.”

The Fairfax Fund has helped Reidenbach continue his research and create educational experiences for his students that wouldn’t otherwise be possible.

“Ultimately, organizations like National Oceanic and Atmospheric Administration would fund the restoration,” Reidenbach explained, “And NSF would fund the basic science, but people like Pete and the Fund are really important for helping us collect the initial data that we need to understand which direction the work needs to go.”

According to Howard Epstein, UVA’s Sidman P. Poole Professor of Environmental Sciences and chair of the College’s Department of Environmental Sciences, the support is critical to making the department a leader in innovative environmental research.

“Private donors like Pete really help us fund work that falls through the cracks when it comes to the large funding agencies, and that gives us the flexibility to do research that might be a little different or allows us to take some chances and explore research opportunities that larger agencies aren’t equipped to support,” Epstein said.

“For the donors,” he added, “It’s an opportunity to support something they’re passionate about or to give something back, and this gives them a chance to play a big part in moving science forward.”

For more information about the Fairfax Marine Research Fund and opportunities to support research at UVA, contact the College Foundation’s Senior Director of Development, Matt McKinney.